Engineering Commons^™

Discharge Correlations For Spillways With Radial Gates, Gerald A. Schohl

International Symposium on Hydraulic Structures

Equations used at the Tennessee Valley Authority (TVA) to compute free and gated (orifice) discharges through spillways with radial gates are presented along with correlations based on TVA model test data for discharge coefficients and submergence factors. The correlations and data may be applicable for estimating discharges through gated spillways that are similar to those at TVA and for which specific model test data are unavailable. Included in this paper, perhaps for the first time in the literature, are correlations and data indicating for given gate opening the headwater at which flow begins the transition from free discharge to gated …

State-Of-The-Practice Review Of Maintenance Closure Structures For Large Spillway Gates, C. M. Johnson, R. T. Indri, F. G. Snider, S. M. Planck, K. F. De Lapp

International Symposium on Hydraulic Structures

Maintenance, remediation, and inspection of large spillway gates are best performed in a dry, dewatered state due to reduced overall cost, worker safety, and improved work quality. Provision for gate dewatering has become a key design consideration for new spillways. Unfortunately, many existing spillways were not originally constructed with gate dewatering capabilities. Therefore, maintenance and inspection work has often been scheduled during planned drawdowns or seasonally low reservoir levels. However, for operators of hydroelectric, flood control, water supply, and multi-purpose dams, artificial drawdowns can significantly impact operations, flood protection, downstream habitat, and revenue generation. Aging gates deteriorate and require significant …

Advanced Gate Operation Strategies In Hec-Ras 5.0, C. R. Goodell

International Symposium on Hydraulic Structures

The Hydrologic Engineering Center’s River Analysis System (HEC-RAS) is designed for computing water surface profiles and inundation maps, but it is also able to handle flow through gated structures using a variety of equation sand techniques. HEC-RAS has a small selection of built-in gate types, representing some of the more common gates that are used for controlling flow at dams and canal structures. Each gate type in HEC-RAS has a set of empirical equations that are used to compute head loss through the structure for a given flow. There are also two operational schemes that can be chosen for gates: …

Designing A Steel Gate Dam Across An Ephemeral River – Tempe Town Lake Dam Design, Stewart S. Vaghti, Dean B. Durkee, Andrew J. Lynch

International Symposium on Hydraulic Structures

After the existing Tempe Town Lake downstream dam failed unexpectedly in 2010, the City of Tempe, AZ, USA was tasked with designing and constructing a replacement dam to maintain their lake, pass flows in the ephemeral Salt River, and deliberately lower to avert flooding. Through an alternatives evaluation process, a hydraulically operated steel gate system was selected from a field of twenty studied alternative configurations to replace the existing rubber bladder system.

The gate design produced eight 32.3 meter (106 foot) long, 6.4 meter (21 foot) tall, and 118,000 kilogram (260,000 pound) steel gates operated by single-acting hydraulic cylinders and …

Usace Portland District Spillway Gate Rehabilitation Program, Laurie Ebner, William Fortuny, David Hamernik, Matthew Hess, Mark Sawka

International Symposium on Hydraulic Structures

The U.S. Army Corps of Engineers (USACE) Portland District has 90 spillway radial Tainter gates. There are 42 gates at the 11 Willamette Valley Basin projects, 5 gates at the two Rogue Basin projects and 43 gates at the two Columbia River projects. Since 2001 there have been various studies, inspections and incidents that have prompted the Portland District to become concerned about the structural integrity and mechanical and electrical reliability of these gates. In 2008, load induced buckling was observed on three of the four Tainter gate end frames at Foster Dam which led to emergency repairs. Additional observations …

Hydraulic Structures-The Future Of Design, Thomas North

International Symposium on Hydraulic Structures

The state of the art of design of hydraulic structures is changing rapidly. Although hydraulic structures include a broad spectrum of applications, there is an increasing need for specialization in planning, design, materials, construction, risk and hazard assessment, aging infrastructure, and lifecycle maintenance.

Today’s role of hydraulic structures involves improving water management practices, water quality, and environmental restoration and protection. Hydraulic design has expanded to include water planning as well as improvements in the design, construction, operation, and maintenance of locks, dams, spillways, and outlet works. The challenges affecting planning and design involve understanding the role of government policies, economics, …

Numerical Investigation Of Usbr Type Iii Stilling Basin Performance Downstream Of Smooth And Stepped Spillways, Daniel Valero, Daniel Bung, Brian M. Crookston, Jorge Matos

International Symposium on Hydraulic Structures

Recent systematic studies on air-water flows have included stepped spillways. However, to date little has been investigated about how the hydraulic conditions on the stepped spillway may affect the design of traditional energy dissipation structures. In this paper, both smooth chute and stepped chute configurations terminating with the USBR type III stilling basin are tested by means of numerical modelling, allowing a qualitative comparison. Unsteady RANS equations have been employed altogether with VOF and RNG k-ε for free surface tracking and turbulence modeling, respectively. Eight different Froude numbers (F) ranging from 3.1 to 9.5 have been analyzed for a type …

Baffle Designs To Facilitate Fish Passage In Box Culverts: A Preliminary Study, H. Chanson, W. Uys

International Symposium on Hydraulic Structures

Waterway culverts and road crossings are very common design in water systems, ranging from rural roads to national highways and urban drainage networks. Engineers and biologists need better, more reliable prediction 'tools' during the design stages to compare the bio-engineering performances of a range of design options. Present expertise in environmental hydraulics of culverts is deficient because of the many empirically-based design guidelines which are sometimes outdated and often inadequate for fish passage. In all the cases, the turbulence of the flowing waters must be optimised efficiently to maximise fish migration. This project focused on the development of simple solutions …

Spillway Rock Scour Analysis - Composite Of Physical & Numerical Modelling, Paradise Dam, Australia, E. J. Lesleighter, E. F.R. Bollaert, B. L. Mcpherson, D. C. Scriven

International Symposium on Hydraulic Structures

A number of problems and solutions of rock scour downstream of spillways have been evaluated using a composite approach, based on the gathering of detailed data from a physical model and utilising those data in a sequence of calibration and application of numerical modelling of the scour. Our paper will describe the application of the Computational Scour Model (CSM - Bollaert, 2002 and subsequent) as the numerical procedure that makes the composite approach a proven methodology for such problems. The paper will focus on a case study application of the procedure based on the experiences of flooding and scour at …

Interaction Of Hydraulic Structures With Air, Water, And Rock: The Challenge Of Researchers And Designers, Anton J. Schleiss

International Symposium on Hydraulic Structures

Since the last ten years, financial crisis has strongly impacted the global economy, which was mainly the result of un-controlled financial speculations at the stock markets highlighted by the revelations regarding offshore companies. Fortunately, the field of construction of large infrastructures, such as hydraulic schemes, has been left relatively untouched by this crisis. In order to stimulate their economies, many governments across the world have injected significant sums into sustainable infrastructures development.

Full Proceedings: Hydraulic Structures And Water System Management, International Association For Hydro-Environmental Engineering And Research, United States Society On Dams

International Symposium on Hydraulic Structures

No abstract provided.

Hydraulic Structures And Water System Management-Ishs2016 In Perspective, Brian M. Crookston, Blake Tullis

International Symposium on Hydraulic Structures

Hydraulic structures are vital features in our water infrastructure, as they help meet the diverse and challenging demands of society, including conveyance, flood protection, environmental and ecological impacts, and systems management. Indeed, there are a number of challenges facing engineers today. This 6^th IAHR International Symposium on Hydraulic Structures (ISHS2016) brought together domestic and international expertise from research, practice, and implementation in a forum for knowledge exchange and networking discussion on critical issues related to hydraulic structure research, performance, operations, maintenance, and community implications. It continued the rich tradition of this series by stimulating interest on advancement in the …

Fiction As A Resource In Participatory Design, Eva Knutz, Tau U. Lenskjold, Thomas Markussen

DRS Biennial Conference Series

In recent years, co-design research has moved into the heart of business and organisational matters of concern. As a consequence of that fact, the idea of what design is capable of evolves into something that does not only encompass product and service design, but also at the same time changes organisations’ way of doing things – or in other words, it challenges the organisational culture and the mindset of the decision-makers as a way towards the successful embedding of a project within the organisation. This paper investigates how the development of a new service design project together with integrated co-design …

Perception, Meaning And Transmodal Design, Mathias Nordvall, Mattias Arvola

DRS Biennial Conference Series

Our perceptual system allows us to experience and make meaning of the world through different modalities. We can move between feeling, seeing and hearing things and still makes sense of our world. Our cognitive activities are transmodal. In interaction design this means that both our design processes and our users’ interactions are transmodal. We have gained insights into how transitions between modalities, both in the design context and in the users’ interaction context, modulate meaning and experience, by analysing three interactive systems: SimProv, VibEd, and Sightlence. We propose that a transmodal design approach facilitate designers to realize the communicative potential …

Design For Resourceful Ageing: Intervening In The Ethics Of Gerontechnology, Elisa Giaccardi, Lenneke Kuijer, Louis Neven

DRS Biennial Conference Series

This paper discusses an innovative approach to the design of technologies for older people. The approach contains a critique of “gerontechnology” as taking decisions out of the hands of older people and materializing what it means to live healthily and well into “foolproof” designs that easily become inappropriate in the variety of situations in which older people end up using them. The proposed design approach focuses on re-delegating such ethical decisions to the point at which technology is used. It does so by considering technologies as resources that can complement the ageing competences of older people and adapt in a …

Well I'Ll Be Damned - Insights Into Predictive Value Of Pedigree Information In Horse Racing, Timothy Baker Mr, Ming-Chien Sung, Johnnie Johnson Professor, Tiejun Ma

International Conference on Gambling & Risk Taking

Fundamental form characteristics like how fast a horse ran at its last start, are widely used to help predict the outcome of horse racing events. The exception being in races where horses haven’t previously competed, such as Maiden races, where there is little or no publicly available past performance information. In these types of events bettors need only consider a simplified suite of factors however this is offset by a higher level of uncertainty. This paper examines the inherent information content embedded within a horse’s ancestry and the extent to which this information is discounted in the United Kingdom bookmaker …

Probability Model Of Corrosion-Induced Cracking Time In Chloride-Contaminated Reinforced Concrete, Chunhua Lu, Jinmu Yang, Ronggui Liu

International Conference on Durability of Concrete Structures

Corrosion-induced concrete cover cracking caused by chloride ion is an important indication of durability limit state for marine reinforced concrete (RC) structures and can ultimately determine the structural service life. In this paper, considering the random nature of factors affecting the corrosion cracking process, a probabilistic model which expands on the deterministic model of cover cracking time is developed by using Monte Carlo simulation technique. The results showed that the time to corrosion cracking can be modelled by the Weibull distribution. Finally, the probabilistic analysis for the cracking time is applied to an in-site RC bridge girder with four different …

Progress Of Carbonation In Chloride Contaminated Concretes, Yaocheng Wang, P. A.M. Basheer, S. Nanukuttan, Y. Bai

International Conference on Durability of Concrete Structures

Concretes used in marine environment are generally under the cyclic effect of CO₂ and chloride ions (Cl^-). To date, the influence of carbonation on ingress of chloride ions in concretes has been widely studied; in comparison, study on the influence of Cl^- on the progress of carbonation is limited. During the study, concretes were exposed to independent and combined mechanisms of carbonation and chloride ingress regimes. Profiles of apparent pH and chloride concentration were used to indicate the progress of carbonation and ingress of Cl^- in concretes. From the apparent pH profile, a carbonation front …

Carbon Fiber As Anode Material For Cathodic Prevention In Cementitious Materials, Emma Qingnan Zhang, Luping Tang, Thomas Zack

International Conference on Durability of Concrete Structures

Cathodic prevention (CPre) technique is a promising method and has been used for the past two decades to prevent steel from corrosion in concrete structures. However, wide application of this technique has been restricted due to high costs of anode materials. In order to lower the cost and further improve this technique, carbon fiber composite anode has been introduced as an alternative anode material with affordable price and other outstanding properties. This paper presents the study of using carbon fiber mesh as anode material for long-term cathodic prevention system and the effect of accelerated current on macro- and microstructure of …

Investigation Of A Novel 3d Non-Destructive Evaluation For Corrosion Process In Reinforced Concrete, Guohao Fang, Biqin Dong, Ningxu Han, Feng Xing

International Conference on Durability of Concrete Structures

X-ray computed microtomography (X-ray μCT) method is proposed to trace the corrosion features of steel bar in cementitious materials. Three-dimensional corrosion morphology (including morphology of steel corrosion, corrosion products and cracks formation) are characterized and reconstructed. Experimental results demonstrate that X-ray μCT can track time-dependent development of corrosion products and the subsequent initiation and propagation of corrosion-induced cracks. In addition, scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) are used to morphologically and chemically analyze the corrosion result. The microscopic analysis result is found to be in a very good agreement with the image analysis measured by X-ray μCT. …

An Experimental Study On Effect Of Steel Corrosion On The Bond–Slip Performance Of Reinforced Concrete, Xiaolin Zhang, Xuebing Liang, Hancheng Huang, Haijun Zhou

International Conference on Durability of Concrete Structures

This paper studied the effects of reinforcement corrosion on bond performance between rebar and concrete. Tests were carried out to evaluate the degradation of bond between reinforcing steel and concrete for different corrosion levels of reinforcing steel. A series of 20 specimens of different concrete strength with various reinforcing steel corrosion levels were designed and manufactured. Each specimen was casted as a 200-mm concrete cube, and a steel rebar was centrally embedded with two stirrups around it. The steel rebar were corroded using an electrochemical accelerated corrosion technique. The corrosion crack opening width and length were recorded after the corrosion …

Threshold Chloride Concentration Of Stainless Steels In Simulated Concrete Pore Solution, Hailong Wang, Jiayan Ling, Xiaoyan Sun

International Conference on Durability of Concrete Structures

To evaluate whether stainless steel can replace carbon steel as rebar in reinforced concrete structures exposed to aggressive environment, the threshold chloride concentration of carbon steel, austenitic and duplex stainless steels were experimentally studied in this paper. The solutions with pH ranging from 9.5 to 13.6 were used herein to simulate the pore liquids in both alkaline and carbonated concretes. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests were carried out in the solutions with chloride concentration ranging from 0 to 5.0M and at a temperature around 25°C. The activation of pitting corrosion was determined when corrosion current increased and …

Corrosion-Induced Concrete Cracking Model Considering Corrosion-Filled Paste, Jianfeng Dong, Yuxi Zhao, Yingyao Wu, Weiliang Jin

International Conference on Durability of Concrete Structures

A T_CP–T_CL model is established to describe the relationship between the thickness of the corrosion-filled paste (CP) and that of the corrosion layer (CL). This model can describe the phenomenon that the corrosion filling in the concrete pores and accumulating at the steel/concrete interface occur synchronously. Based on the T_CP–T_CL model, a corrosion-induced concrete cracking model, which can quantitatively consider corrosion-filled paste at concrete/steel interface, is proposed. Combined with damage analysis in corrosion-induced cracking process of concrete cover, the model is developed to describe the quantity of steel corrosion required to crack …

The Compressive Strength Of Cement–Slag–Calcium Sulphoaluminate Ternary System, Hu Shi, Jun Wang, Zhuqing Yu, Xiaodong Shen

International Conference on Durability of Concrete Structures

At present, there is an increasing interest on the use of calcium sulphoaluminate (C₄A₃$) in cement. In this paper, pure mineral of sulphoaluminate (C₄A₃$) was prepared in laboratory. Different dosages of steel slag and C₄A₃$ were blended into cement. The aim of this paper is to investigate the compressive strength of this ternary system. The test results show that the addition of C₄A₃$ can improve the strength of cement. Larger C₄A₃$ dosage (7%) may reduce the 28 days strength. The …

Potential For Alkali–Silica Reaction In Radiation Shielding Concrete Containing Special Aggregates, Daria Jóźwiak-Niedźwiedzka, Michał A. Glinicki, Karolina Gibas

International Conference on Durability of Concrete Structures

In the present study, the potential for the alkali–silica reaction (ASR) in radiation shielding concrete containing special aggregates is presented. The tests were performed on two kinds of aggregate: (1) high-density aggregate to absorb the gamma radiation (barite, magnetite, and hematite) and (2) mineral with high bound water content to attenuate the neutron flux (serpentinite). The optical microscopy in transparent light on thin sections, XRD and XRF method, was used to assess the mineral composition of aggregates. ASTM C1260 test method for potential alkali reactivity of aggregates was applied also to investigate the effect of different content and crystal size …

Effect Of Superabsorbent Polymers (Sap) On Fresh State Mortars With Ground Granulated Blast-Furnace Slag (Ggbs), Fernando Do Couto Rosa Almeida, Agnieszka Joanna Klemm

International Conference on Durability of Concrete Structures

Although cementitious materials are the main construction materials and worldwide produced, there is still a major concern about their sustainability and durability, especially in terms of conserving resources, reducing wastes, and decreasing the environmental impacts of repair and replacement. In general, cementitious materials are very susceptible to cracking provoked by autogenous shrinkage due to their associated self-desiccation process. The problem is even more critical in concrete with blended cements, including Portland cement with ground granulated blast-furnace slag (GGBS). The current paper evaluates efficiency of superabsorbent polymers (SAP) as internal curing agents; shrinkage reduction in mortars with different levels of cement …

Designing Repeatable Self-Healing Into Cementitious Materials, Mo Li, Shuai Fan

International Conference on Durability of Concrete Structures

Designing self-healing into cementitious materials can open a new world of opportunities for resilient concrete infrastructure under service loading conditions. The self-healing process should be robust as well as repeatable, allowing for self-repair after multiple damage events. The repeatability poses great challenges when self-healing strategies mainly rely on the formation of low-strength calcium carbonate healing product, complicated by the localized cracking behavior of cementitious materials. This study aims at formulating a new cementitious material system with designed physical and chemical characteristics that favour repeatable self-healing. Advanced experimental methods, coupled with micromechanics theory, are adopted to probe and design repeatable self-healing …

Progress In Durability Study Of Frp Materials, Zeng-Zhu Zhu, Ying-Wu Zhou, Li-Li Sui, Feng Xing, Jia Du

International Conference on Durability of Concrete Structures

During the past decades, FRP strengthened RC structures have attracted worldwide interest in both application and research. Nowadays, as more and more infrastructures are being suffered from severe corrosions due to harsh and extreme environments, the durability of FRP strengthened RC structures has generally emerged as the most important issue in research. Thus, the paper presents the latest progress in durability study of the FRP materials through an in-depth review and analysis on existing extensive investigations. The time-dependent performances of two types of FRP materials of carbon FRP (CFRP) and glass FRP (GFRP) under severe environments of humidity, high temperature, …

Durability-Based Optimal Design Methodology For Rc Members In Corrosive Environment, Saeid A. Alghamdi, Shamsad Ahmad, Adamu Lawan

International Conference on Durability of Concrete Structures

No abstract provided.

Investigation Of The Spatial Variability Of Steel Weight Loss And Corrosion Cracking: A Novel X-Ray Technique, Sopokhem Lim, Haitao Jiang, Mitsuyoshi Akiyama

International Conference on Durability of Concrete Structures

The performance of corrosion-affected RC members depends strongly on localized damages of reinforcement. Therefore, modeling the spatial variability of steel corrosion is very important for the assessment of the remaining service life of corroded structures or time for maintenance. To study the changes of spatial variability of steel weight loss over time, a continuous monitoring is necessary. In this paper, a novel procedure of X-ray technique application in monitoring the spatial growth of a corroded bar in a RC specimen is demonstrated along with the digital image processing of X-ray images to estimate the steel weight loss. The relationship of …